Immunohistochemical Study of Immunocompetent Cell Populations Associated with Periodontal Disease Activity

Abstract

Immunocompetent cell populations associated with periodontal disease activity were studied by means of immunohistochemical characterization of the gingiva, with or without deep periodontal pockets, in various clinical stages.
Serial paraffin sections were prepared from gingiva fixed by the AMeX method. Cell species were identified with monoclonal antibodies reactive with B cells, T cells and macrophages and classes of immunoglobulins in plasma cells were determined with polyclonal class specific antibodies.
The specimens were classified into three groups according to periodontal therapy history and probing pocket depth: P-1; untreated gingivae with pockets 6-8mm in depth, P-2; gingivae after initial preparation with pockets 6. `8mm in depth. There were some improvements in clinical symptoms in this group. P-3; clinically cured gingivae with pockets 2-3mm in depth during the maintenance phase. Gingivae from patients with chronic gingivitis were also examined.
Plasma cells, B cells and macrophages were more numerous in P-1 than in P-3 or the gingivitis group. P-3 resembled chronic gingivitis in that T cells were dominant. In P-1, T cells, B cells and macrophages were localized preferentially in the connective tissue subjacent to the pocket epithelium, while plasma cells were dominant in the connective tissue which was at some distance from the epithelium. Inflammatory infiltrates in P-2 were similar to those in P-1 but not to those in P-3.
Thus, the clinical improvement observed after initial preparation of deep pockets did not result in an immunohistological alteration as demonstrated in P-3 during the maintenance phase. These results suggest that B cells and macrophages which react with microflora and antigenic substances in pockets correlate more closely with disease activity and, after initial preparation, gingiva with deep pockets still carry the risk of bursting during periods of disease activity.